over·strung /-ˈstrʌŋ/
  (a.)過度緊張的
  overstrung
       adj 1: being in a tense state [syn: edgy, high-strung, highly
              strung, in suspense(p), jittery, jumpy, nervy,
               restive, uptight]
       2: too tightly strung; "an overstrung archery bow"